Dumb foreigner can't figure out boiler controls

Bendy_House

As said above, BF - you no longer have a combi boiler which heats ONLY the water you are actually drawing from a tap. Instead you now have what's called a 'heat only' boiler, a 'normal' type!

In a cupboard somewhere, you will find a hot water cylinder. This holds the pre-heated hot water for your taps and shower. It is heated up IN ADVANCE by this boiler, at times set on that programmer.

It should be well insulated, so if heated up ONLY in the morning, it should still be pretty hot in the evening. This depends, of course, on how much water you draw from it.

How you time this to heat your HW cylinder will depend on your home life. If folk like a shower in the morning, then you should definitely have it coming on for at least a half-hour just before anyone gets up.

If more than one person has a shower/if these showers are looong, then it would make sense to have the HW still running until all the showers are done - there should still be hot water left for the rest of the day.

Again, you'll probably want a 30-minute boost of HW taking place before folk come home in the afternoon.

Basically, you experiment until you find whether you run out of hot water at some point, and then need to add to these timings.

If your household is full and very busy all day, then you might decide to just leave it on 'ON' so that you always have HW at all times. Your hot cylinder will have a temperature thermostat fitted to its side, probably set at around 65oC, and this will/should prevent your cylinder from becoming any hotter than this, and it'll automatically shut off the boiler when that temp is reached. When the temp drops, the boiler will come back on.

Because some heat is always lost from the HW cylinder, then you will be using more gas to keep the cylinder at full temp, so this is not usually recommended. It depends on your personal family circumstances.

FreeBear

Bendy_House said: Your hot cylinder will have a temperature thermostat fitted to its side, probably set at around 65oC, and this will/should prevent your cylinder from becoming any hotter than this, and it'll automatically shut off the boiler when that temp is reached. When the temp drops, the boiler will come back on.

The HW tank should have a thermostat - Unfortunately, not all do. If the OP doesn't have one, then having one fitted should be a priority. And there is no need to set it at 65°C - If Legionella is a concern, maintaining a water temperature of 55°C will kill still the bacteria and reduce the gas consumption.

breaking_free

Oho so that's the answer - not a combi boiler after all (told you I was a dumb foreigner!) There is probably a hot water tank in the loft as some of you have suggested. I'll have to get a ladder and take a looksie some time. 

Thanks for all the helpful advice. Now that I've got my head around why a "combi boiler" (not!) has hot water controls I'll make myself up a plan for setting the best usage times. Cheers MSE team.

FreeBear

breaking_free said: Oho so that's the answer - not a combi boiler after all (told you I was a dumb foreigner!) There is probably a hot water tank in the loft as some of you have suggested. I'll have to get a ladder and take a looksie some time.

Any tank in the loft is likely to be a header tank. The HW cylinder will be in an airing cupboard (next to the bathroom perhaps).

It will be surrounded by pipes & cables, so should be easy to spot. Once you have found it, look for a switch with a red light on it - Should be labeled "Immersion Heater" - Make sure it is turned off, and it will save you shed loads of money on the electricity bill.

kobe84

breaking_free said:

Oho so that's the answer - not a combi boiler after all (told you I was a dumb foreigner!) There is probably a hot water tank in the loft as some of you have suggested. I'll have to get a ladder and take a looksie some time. 

Thanks for all the helpful advice. Now that I've got my head around why a "combi boiler" (not!) has hot water controls I'll make myself up a plan for setting the best usage times. Cheers MSE team.

As mentioned above, as this is a conventional boiler you will have a cold water header tank, probably in the loft that will feed into the water cylinder below, which will likely be in an airing cupboard somewhere rather than the loft.

breaking_free

I haven't looked in the loft yet (don't have a ladder) but there's no sign of a hot water cylinder anywhere. I'm in a bungalow if that's significant at all.

coffeehound

There might not be a cold header tank if it's an unvented system ..

NeverTooLate

breaking_free said:

I haven't looked in the loft yet (don't have a ladder) but there's no sign of a hot water cylinder anywhere. I'm in a bungalow if that's significant at all.

It is possible that both the cold and hot tanks are in the loft. We had that setup in our last house - there was enough head space in the loft to put the cold tank above the hot.

kobe84

breaking_free said:

I haven't looked in the loft yet (don't have a ladder) but there's no sign of a hot water cylinder anywhere. I'm in a bungalow if that's significant at all.

It may well be up in the loft in that case.

Bendy_House

Can't wait to find out where this cylinder is!

Up in t'loft there could be a wee F&E tank, a large CWS tank and a hot cylinder. Or, if the cylinder is unvented, there won't be a CWS. And, if the system is sealed, there won't even be a small F&E, but instead an EV with a pressure gauge - but I doubt it.

Unless this bungalow is particularly small and with little storage space, I'd still expect BF to find their cylinder in a cupboard somewhere; it's a shame to lose the warmth given out by these tanks, as it provides for a good 'airing' cupboard.

What a mystery